Diversity of the 'Candidatus Phytoplasma asteris' and 'Candidatus Phytoplasma fraxini' isolates that infect urban trees in Bogotá, Colombia.

Phytoplasmas have been associated with a disease that affects trees of at least 11 species from different botanic families in Bogotá, Colombia. 'Candidatus Phytoplasma asteris' and 'Candidatus Phytoplasma fraxini' are the major groups of phytoplasma in the area of Bogotá. In this study, the genetic diversity within 'Ca. P. asteris' and 'Ca. P. fraxini' was studied in five urban tree species: Croton species (Euphorbiaceae), Fraxinus uhdei (Oleaceae), Magnolia grandiflora (Magnoliaceae), Populus nigra (Salicaceae) and Quercus humboldtii (Fagaceae). Analyses of the 16S rRNA gene using nested PCR, RFLP and sequencing showed that phytoplasmas of 'Ca. P. asteris' could be assigned to: subgroup 16SrI-B; a new subgroup named 16SrI-AF, with a restriction pattern similar to that of 16SrI-B; and a new subgroup named 16SrI-AG, with a restriction pattern similar to that of 16SrI-K and 16SrI-AH with a restriction pattern similar to that of 16SrI-AC. 'Ca. P. fraxini' isolates belonged to a new subgroup named 16SrVII-G, with a restriction pattern similar to that of 16SrVII-A. To complement the identification of the phytoplasma strains, we amplified nonribosomal genes such as leuS and secA. Unexpectedly, it was observed that in 16 trees in which 16S rRNA gene analysis showed the presence of 'Ca. P. fraxini' only, the leuS or secA primers amplified sequences exclusively affiliated to 'Ca. P. asteris. In those plants, sequences belonging to 'Ca. P. fraxini' leuS or secA genes were not amplified. The present work contributes to the identification of novel strains of both species in Colombia, and supports previous suggestions that phytoplasmas in South America are highly variable.

Tracing Mycobacterium ulcerans along an alimentary chain in Côte d'Ivoire: A one health perspective.

BACKGROUND: Mycobacterium ulcerans is an environmental mycobacterium responsible for an opportunistic, noncontagious tropical infection named Buruli ulcer that necrotizes the skin and the subcutaneous tissues. M. ulcerans is thought to penetrate through breached skin after contact with contaminated wetland environments, yet the exact biotopes where M. ulcerans occurs remain elusive, hence obscuring the epidemiological chain of transmission of this opportunistic pathogen. METHODOLOGY/PRINCIPAL FINDINGS: Polymerase chain reaction investigations detected M. ulcerans in 39/46 (84.7%) rhizosphere specimens collected in 13 Buruli ulcer-endemic areas in Côte d'Ivoire and 3/20 (15%) specimens collected in a nonendemic area (P = 5.73.E-7); only 3/63 (4.7%) sediment specimens from sediment surrounding the rhizospheres were positive in endemic area (P = 6.51.E-12). High-throughput sequencing further detected three PCR-positive plants, Croton hirtus, Corton kongensis and Oriza sativa var. japonica (rice), in the rectal content of two M. ulcerans-positive wild Thryonomys swinderianus grasscutters that were hunted in Buruli ulcer-endemic areas, while no PCR-positive plants were detected in the rectal content of two negative control animals that were farmed in a nonendemic area. CONCLUSIONS/SIGNIFICANCE: Our data suggest an alimentary chain of transmission of M. ulcerans from plants to T. swinderianus grasscutters and people that utilize T. swinderianus as bush meat in Buruli ulcer-endemic areas in Côte d'Ivoire. Guidance to adopt protective measures and avoid any direct contact with potentially contaminated rhizospheres and with grasscutter intestinal content when preparing the animals for cooking should be established for at-risk populations.

Cytotoxic activity of four xanthones from Emericella variecolor, an endophytic fungus isolated from Croton oblongifolius.

Four xanthones were isolated from mycelia of Emericella variecolor, an endophytic fungus isolated from the leaves of Croton oblongifolius. Their structures were elucidated by spectroscopic analysis to be shamixanthone, 14-methoxytajixanthone-25-acetate, tajixanthone methanoate, and tajixanthone hydrate. All compounds were tested for cytotoxic activity against various human tumor cell lines including gastric carcinoma, colon carcinoma, breast carcinoma, human hepatocarcinoma, and lung carcinoma. The antitumor activities of these xanthones were compared with that of doxorubicin hydrochloride, a chemotherapeutic substance. All of them showed moderate activities and were selective against gastric carcinoma, colon carcinoma, and breast carcinoma. Only tajixanthone hydrate exhibited moderate activity against all cancer cell lines. Furthermore, under the test conditions it was found that 14-methoxytajixanthone-25-acetate and tajixanthone hydrate are almost as active as doxorubicin hydrochloride against gastric carcinoma (KATO3) and breast carcinoma (BT474).

Control microbiológico y evaluación de la actividad antibacteriana en vitro de croton lechleri Sangre de grado / Microbiological control and evaluation of the antibacterial activity in vitro of croton lechleri Blood of degree

Se realizó el control microbiológico de extractos de croton lechleri expedido en el comercio bajo el nombre de "Sangre de grado". Además se evaluó la actividad antibacteriana del mismo. Se analizaron 50 muestras provenientes de los departamentos de Lima, San Martín, Huánuco y Ucayali. De 47 muestras provenientes de Lima, 18 por ciento fueron positivas a coliformes totales y un 9 por ciento a coliformes fecales. Se determinó una marcada actividad antibacteriana frente a Staphylococcus aureus en extractos provenientes de Ucayali en diluciones del 50 por ciento y 100 por ciento.

The microbiological control of extracts of Croton lechleri expended in the comercialization below the name of "Sangre de Grado" was realized. Also was evaluated the antibacterial activity of the same. 50 samples proceeding from the departrnents of Lima, San Martin, Huanuco and Ucayali were analized. From 47 samples proceeding from Lima, 18% were positives to totals coliforms and 9% to fecals coliforms. A marked antibacterial activity agains Staphylococcus aureus in extracts proceeding from Ucayali in dilution of 50 % and 100 % was determinated.